Methods for the synthesis of large numbers of diverse compounds that can be screened for various possible physiological or other activities are advantageous (Ellman, et al. Chem. Rev. 96, 555-600 (1996)). Techniques have been developed in which individual units are added sequentially as part of the chemical synthesis to produce all, or a substantial number, of the possible compounds which can result from all the different choices possible at each sequential stage of the synthesis. Many diverse compounds are produced by a series of reactions of a multiplicity of synthons in various combinations. Each compound in a combinatorial library results from the reaction of a subset of synthons. For these techniques to be successful, the compounds should be amenable to methods by which one can determine the structure of the compounds so made. A premier example of such techniques is the production of oligonucleotide "tags" in parallel with oligopeptide compounds of interest (Brenner and Lerner Proc. Natl. Acad. Sci. USA 81, 5381-83 (1992) and WO 93/20242). Methods for particle-based synthesis of random oligomers wherein identification tags on the particles are used to facilitate identification of the synthesized oligomer sequence are known (WO 93/06121). A detachable tagging system that is useful in sequential synthesis of large numbers of compounds has been disclosed (Ohlmeyer et al., Proc. Natl. Acad. Sci. USA, 90, 10922-10926 (1993)).